Wheeled vehicle suspension

ABSTRACT

A wheeled vehicle suspension positions tandem axle assemblies on the vehicle by way of semi-elliptic springs normally urging said tandem axle assemblies toward said vehicle so as to lift them from a road surface. Air bags are positioned between the tandem axle assemblies and the vehicle and means for inflating and deflating the air bags permit either or both of the tandem axle assemblies to be lifted from a road surface or engage therewith in a weight carrying relation to said vehicle.

1 Oct. 2, 1973 WHEELED VEHICLE SUSPENSION United States Patent Bilas2110/81 R 280/1 12 R Turner 280/81 R 5/1964 Granning ABSTRACT A wheeledvehicle suspension positions tandem axle assemblies on the vehicle byway of semi-elliptic springs normally urging said tandem axle assembliestoward said vehicle so as to lift them from a road surface. Air bags arepositioned between the tandem axle assemblies'and the vehicle and meansfor iriflating and deflating the air bags permit either or both of thetandem axle assemblies to be lifted from a road surface or engagetherewith in a weight carrying relation to said vehicle.

4 Claims, 3 Drawing Figures Primary Examiner-Kenneth H. Betts AssistantExaminer-Reinhard Eisenzopf At0rneyWebster B. Harpman 280/104.5 R 180/22D X Michael Bilas, 2730 Columbiana-New Castle Rd., New Springfield, Ohio44443 Oct. 18, 1971 l80/24.09, 280/124 F, 280/81 R References CitedUNITED STATES PATENTS 8/1949 Gentry.......l.................

9/1952 Ronning..

11/1959 Norrie............

6/1961 Johannsen lnventor:

Appl. No.: 189,952

U.S. Cl. Int Cl Field of Search......................

180/24.09, 22 D, 22 E; 280/124 F, 81 R [22] Filed:

PATENTEDUBT 2191s saw 1 or R 3 1 M8 L E A H w M ATTORNEY PATENTEDBET2191s saw 2 OF 2 AT TORNE WI-IEELED VEHICLE SUSPENSION BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates to wheeledvehicles and more particularly to suspensions for wheeled vehicles suchas trucks and trailers.

2. Description of the Prior Art Prior suspensions of this type haveemployed springs normally urging the wheeled axle assemblies toward theroad surface and springs normally urging the wheeled axle assembliesaway from the road surface and which latter arrangements incorporatedair bags for urging the wheeled axle assemblies toward the road surfacein the supporting relation to the vehicle.

(See US. Pat. Nos. 2,989,300, 3,063,732, 3,093,388, 3,096,995 3,133,745and 3,285,621).

This invention eliminates some of the problems heretofore associatedwith the prior art vehicle suspensions and provides an arrangementwherein the tandem axle assemblies may be driven when in road engagingposition and disconnected from the drive means when in elevated relationto the road. The invention makes possible the use of a plurality ofwheeled axle assemblies in tandem relation to a vehicle, several ofwhich may be elevated with respect to the road as desired.

SUMMARY OF THE INVENTION A wheeled vehicle suspension is disclosed whichenables at least a pair of tandem axle assemblies of a vehicle to beselectively elevated with respect to a road surface or engagedthereagainst in load carrying relation to said vehicle. The tandem axleassemblies are secured to the vehicle by springs normally urging theaxle assemblies toward the vehicle and away from the supporting roadsurface and inflatable air bags between each of the tandem axleassemblies and the vehicle served to move the tandem axle assembliestoward the road surface as desired. The disclosure incorporatesautomatically actuating drive means for one of the tandem axleassemblies whereby it becomes a driven axle assembly when in engagementwith the road surface and which driven connection is separated when itis in elevated relation to the road surface.

DESCRIPTION OF THE DRAWING FIG. 1 is a side elevation of a wheeledvehicle with parts in cross section and parts broken away.

FIG. 2 is a symbolic diagram of an air inflation system for the air bagsseen in FIG. 1 of the drawing.

FIG. 3 is a side elevation with parts broken away illustrating analternate means of assuring tilting motion to a driven axle assembly asseen in FIG. 1 of the drawmg.

DESCRIPTION OF TI-IE PREFERRED EMBODIMENT In the form of the inventionchosen for illustration, and as seen in FIG. I of the drawing, a vehicleis provided with spring suspension units 11 and 12 and a plurality ofwheeled axle assemblies A, B, and C which are movably mounted on thevehicle 10 thereby. The wheeled axle assembly A includes a driven axle14, a differential 15 for driving the same and a drive shaft 16 forimparting movement thereto. Shackle bolts 17 mount the axle 14 on a leafspring 18 which in turn is pivoted to the spring suspension units 11.

The differential 15 is provided with a power take-off 19 to which auniversal joint 20 is affixed. A driven shaft 21 continues from theuniversal joint 20 and the outer end thereof is splined as at 22 and thesame is telescopically engaged in a tubular member 23, the innermost endof which is splined as at 24. The tubular member 23 is attached to oneportion of a secondary universal joint 25 and the same connects with asecondary differential 26 on an axle 27 in the wheel and axle assemblyB, which is spaced longitudinally of the wheel and axle assembly A. InFIG. 1 of the drawing the wheel and axle assembly B is shown in anelevated relation to the road surface R, and it will be seen that theaxle 27 thereof is secured by a shackle bolt 28 to one end of a leafspring 29, the central portion of which is secured by a mounting 30 tothe spring suspension unit 12. The spring 29 normally urges the endsthereof and the wheel and axle assemblies B and C upwardly towards thevehicle 10.

The end of the spring 29, which is secured to the axle 27 of the wheeland axle assembly B, is engaged against an air bag structure 31 which isshown in FIG. 1 in deflated condition. The air bag structure 31 includesa mounting 32 secured to the vehicle 10. The other end of the leafspring 29 is secured to an axle 33 in the wheel and axle assembly C by ashackle bolt 34 and a secondary inflatable air bag structure 35 ispositioned thereabove and attached to the vehicle 10 by a mounting 36.The air bags 35 are illustrated in inflated condition whereby the wheeland axle assembly C is moved downwardly into engagement with the road Rso as to assist in supporting the vehicle 10.

It will be understood by those skilled in the art that each of the axles14, 27, and 33 has two ground engaging wheels thereon, and that the axleI4 is connected to the spring suspension units 11 by a pair of thesprings 18 as customary in the art.

The axles 27 and 33 are supported on the opposite ends of a pair of leafsprings 29, and there are pairs of the air bags 31 and 35 on each ofsaid axles. By referring now to FIG. 2 of the drawing a symbolicillustration of means for inflating and deflating the air bags 31 and 35individually may be seen. The same comprises a compressor 37,a pressureregulating valve 38, a gauge 39, a pair of control valves 40 and 41, andinterconnecting air tubing 42 establishing communication between thecompressor 37 and the pairs of air bags 31 and 35 respectively. Bymanipulating the valves 40 and 41, the wheel and axle assemblies B and Cmay be raised or lowered as will occur to those skilled in the art.

It will also occur to those skilled in the art that the wheel and axleassembly B may be an idler wheel assembly comparable with the wheel andaxle assembly C, rather than the driven wheel and axle assembly asillustrated and hereinbefore described and in such event the splinedtelescopic drive shaft including the parts 21 and 23 is unnecessary asis the secondary differential 26. When the wheel and axle assembly isdriven, as illustrated in FIG. 1 and heretofor described, auxillarymeans may be employed to insure the tilting of the axle 27 and thedifferential thereof so as to separate the splined portions of thetelescopic drive shaft. By referring now to FIG. 3 of the drawing, sucha construction may be seen. In the FIG. 3, the first drive shaft of avehicle is indicated by the numeral 43 and it is connected by auniversal joint 44 to a differential 45 on a first driven axle 46. Apower take-off 47 is connected to a secondary universal joint 48 and thesame is connected with a third universal joint 49 by way of a telescopicdriven shaft 50, the respective portions of which are splined forselective engagement and disengagement depending upon the degree oftelescopic engagement as will occur to those skilled in the art. Asecondary differential 51 on a second axle 52 has an arm 53 extendingupwardly therefrom and pivotly connected to one end of a piston rod 54,which is part of a piston and cylinder assembly 55, the other end of thecylinder being pivoted, mounted to a bracket 56 on the vehicle on whichthe wheeled vehicle suspension is employed. It will occur to thoseskilled in the art that by changing the position of the piston andpiston rod 54 in the cylinder 55 the differential 51 will tilt relativeto the axle 52 and thereby lengthen or shorten the telescopic driveshaft 50 and engage and disengage the splined portions thereof. Thoseskilled in the art will thus observe that when the axle 52 is elevatedand tilted, the telescopic drive shaft 50 positively disconnects so thatdriving motion from the drive shaft 43 does not extend to the secondaxle 52.

It will thus be seen that an improved and simplified wheeled vehiclesuspension has been disclosed which enables an operator of a truck ortruck-trailer combination to lift one or two axles from groundengagement when in a no-load condition and thereby cut down on wear onthe wheel and axle assemblies, which would otherwise take place, as wellas reduce the number of tion has been illustrated and described, it willbe apparent to those skilled in the art that various changes andmodifications may be made in the invention without departing from thespirit of the same and having thus described my invention,

What I claim is:

1. A wheel suspension for a vehicle including first and second wheel andaxle assemblies underlying said vehicle in tandem arrangement, springmeans extending between said first and second wheel and axle assemblies,and means on said vehicle engaging said spring means centrally thereof,said spring means normally urging said wheel and axle assemblies towardssaid vehicle and air bags positioned between said vehicle and each ofsaid wheel and axle assemblies for moving said wheel and axle assembliesaway from said vehicle when inflated, and means for inflating anddeflating said air bags.

2. The wheel suspension of claim 1 and wherein said spring meansconsists of a pair of leaf springs having a semi-U shaped configurationin unloaded condition with said wheel and axle assemblies secured to theopposite ends thereof.

3. The wheel suspension of claim 1 and wherein the means on the vehicleengaging the spring means comprises members extending downwardly fromsaid vehicle and attached to said spring means centrally thereof so asto space said springs with respect to said vehicle.

4. The wheel suspension of claim 1 and wherein one of said wheel andaxle assemblies is driven, and means including a drive shaft anddifferential are employed for driving the same, and a separableconnection in said drive shaft is arranged to disconnect said drivenwheel and axle assembly from said drive shaft when said wheel and axleassembly is elevated.

1. A wheel suspension for a vehicle including first and second wheel andaxle assemblies underlying said vehicle in tandem arrangement, springmeans extending between said first and second wheel and axle assemblies,and means on said vehicle engaging said spring means centrally thereof,said spring means normally urging said wheel and axle assemblies towardssaid vehicle and air bags positioned between said vehicle and each ofsaid wheel and axle assemblies for moving said wheel and axle assembliesaway from said vehicle when inflated, and means for inflating anddeflating said air bags.
 2. The wheel suspension of claim 1 and whereinsaid spring means consists of a pair of leaf springs having a semi-Ushaped configuration in unloaded condition with said wheel and axleassemblies secured to the opposite ends thereof.
 3. The wheel suspensionof claim 1 and wherein the means on the vehicle engaging the springmeans comprises members extending downwardly from said vehicle andattached to said spring means centrally thereof so as to space saidsprings with respect to said vehicle.
 4. The wheel suspension of claim 1and wherein one of said wheel and axle assemblies is driven, and meansincluding a drive shaft and differential are employed for driving thesame, and a separable connection in said drive shaft is arranged todisconnect said driven wheel and axle assembly from said drive shaftwhen said wheel and axle assembly is elevated.